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101.
We have reported our experience with splenectomy in fifty patients less than fourteen years old. The indications, results, and complications were enumerated. These data were then correlated with the recent literature regarding pediatric splenctomy. Of special note is the problem of immunologic incompetency associated with splenectomy in the patients less than five years old. 相似文献
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The feces of 318 healthy adults were examined for L. monocytogenes by means of the cold enrichment and of two different selective media (nalidixic acid-trypaflavin-serum agar; Braveny medium). 15 persons (4.7 percent) proved to be carriers. Three of the 15 strains only caused hemolysis on sheep blood agar and belonged to serotypes 1/2b, 1/2c and 3c. The nonhemolytic strains without exception belonged to serotypes 4f and 4g. The Braveny medium proved to be superior to the nalidixic acid-trypaflavin-serum agar for isolating L. monocytogenes from feces. 相似文献
104.
A case of multiple adenocarcinoma arising from the kidney, bladder, and prostate is presented with a relevant discussion of the possible factors of pathogenesis. A staged approach of radical extirpative surgery is suggested. 相似文献
105.
H Biran JL Moake RC Reed JU Gutterman EM Hersh EJ Freireich GM Mavligit 《Canadian Metallurgical Quarterly》1976,34(5):493-499
Serum complement levels were assayed in 26 patients with disseminated cancer, who received immunotherapy with infusion of C. parvum. Complement activation, indicated by the consumption of C3 or C4 or both, was found in 46% of the patients. Serum samples showed direct correlation between decreased C3 and conversion of C3 proactivator, whereas such conversion did not occur when C4 alone was decreased. It is concluded that the bypass (properdin) pathway was activated in patients in whom C3 consumption was detected, while the classical (C1) pathway was activated in the patients with C4 consumption unaccompanied by C3 decrease. Direct correlation was observed between delayed cutaneous hypersensitivity reactions to recall antigens and the incidence of C. parvum-associated complement activation. 相似文献
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Hydrolysis of the gentisate ring-cleavage product, maleylpyruvate (cis-2,4-diketohept-5-enedioic acid), was shown to be catalyzed by an enzyme, maleylpyruvate hydrolase 11, in Pseudomonas alcaligenes (P25X1) after growth with 3-hydroxybenzoate. This activity was separated from fumarylpyruvate hydrolase activity during the course of its purification which accomplished an approximately 50-fold increase in specific activity. An apparent molecular weight of 77,000 was assigned on the basis of Sephadex G-200 chromatography. Despite the presence of up to three similarly migrating bands of protein on polyacrylamide-gel electrophoresis of the purified enzyme, at least two of these bands possessed maleylpyruvate hydrolase activity. Electrophoresis on sodium dodecyl sulfate-polyacrylamide before and after reduction with mercaptoethanol gave a principal band of molecular weight of 33,000 (and a minor band of molecular weight 50,000). A number of substituted maleylpyruvates also served as substrates for maleylpyruvate hydrolase 11, but maleylacetoacetate and fumarylpyruvate were not attacked. Fumarylpyruvate hydrolase was purified approximately 40-fold to give a single band on polyacrylamide gels and with an apparent molecular weight of 73,000 by Sephadex G-200 chromatography. Upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis before or after reduction with mercaptoethanol, a subunit molecular weight of 25,000 was obtained. Neither maleylpyruvate nor fumarylacetoacetate served as substrates for fumarylpyruvate hydrolase. The activities of both maleyl- and fumarylpyruvate hydrolases were stimulated by Mn(2+) ions. Reasons are discussed for the presence of both enzyme activities, one of which appears to be redundant. 相似文献
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A comparison was made of the esterase and activator activities of the various activated forms of human plasminogen and their streptokinase complexes with Nalpha-Cbz-L-lysine-p-nitrophenyl ester as the substrate. The steady state kinetic properties of Glu- and Lys-plasmins, and Glu- and Lys-plasminogen-streptokinase complexes were identical, while the Lys-plasmin-streptokinase complex showed a 2-fold increase in Km with the same kcat and a 3-fold increase in Ki for the competitive inhibitor leupeptin. Lys-plasminogen (zymogen with an active site) was prepared which incorporated 0.7 mol of [3H]idisopropyl phosphorofluoridate and 0.43 mol of p-nitrophenyl-p'-guanidinobenzoate/mol of protein. The Km for Lys-plasminogen was 3-fold higher than that of Lys-plasmin, and its maximum velocity 10-fold lower. The steady state kinetic parameters of a plasmin-derived light (B) chain (CmCys)3, and a derived equimolar light (B) chain-streptokinase complex (CmCys)3, isolated from human plasmin and equimolar plasmin-streptokinase, or plasminogen-streptokinase, complexes, respectively, were determined. When the light (B) chain-streptokinase complex is isolated from its parent complexes, there is a complete retention of the original parent's esterase activities, with respect to Km and kcat, and interaction with the competitive inhibitors benzamidine and leupeptin. The plasmin-derived light (B) chain does not retain its parent esterase activities. This chain has very similar kinetic properties to Lys-plasminogen except that streptokinase, in an equal molar amount, does not impart full esterase activity to the light (B) chain whereas the zymogen can be completely activated by streptokinase. The kcat of the plasmin-derived light (B) chain, and its streptokinase complex can be enhanced by 50 and 30%, respectively, in the presence of 10(-4) M leupeptin, a competitive inhibitor of plasmin, attesting to the increased structural flexibility within the active site of this enzyme species. Urokinase hydrolyzes Nalpha-Cbz-L-lysine p-nitrophenyl ester efficiently with a kcat/Km of one-third that of plasmin. The human plasminogen activator activities of various activated forms of human plasminogen and their equimolar streptokinase complexes were compared in a kinetic assay. The Lys-plasmin-streptokinase complex, and streptokinase were the least active of the activator species and were approximately equal in their activator activities. Glu- and Lys-plasminogen-streptokinase complexes had approximately 1.5 times the activity of streptokinase, whereas the equimolar light (B) chain-streptokinase complexes had approximately 2- to 3-times the activator activity of streptokinase. Since the esterase activity remained unchanged, this indicates a greater degree of specificity in the active site of the equimolar light (B) chain-streptokinase activator complex. Urokinase proved to be a poor activator species... 相似文献